1. Field of the Invention
The present invention relates to an image processing device, method and an imaging device, and in particular to a technique of eliminating an influence of a mixed color or the like between each of pixels of a mosaic image corresponding to a color filter array arranged on an imaging element of a single plate.
2. Description of the Related Art
Generally, in an imaging element having a mosaic color filter array, a mixed color is caused by light leaked from an adjacent pixel.
If an image is formed by applying digital signal processing to RGB color signals with many mixed colors, color reproducibility (image quality) is deteriorated. In addition, there is a problem in which it is impossible to accurately calculate a WB gain for white balance (WB) correction from RGB color signals with many mixed colors.
Conventional techniques of eliminating a mixed color component from a color signal including a mixed color component are described in Japanese Patent Application Laid-Open No. 2007-142697 (PTL 1) and Japanese Patent Application Laid-Open No. 2010-130583 (PTL 2).
A signal processor described in PTL 1 is configured to apply mixed color correction processing to a signal of a correction object pixel based on a signal of each of four peripheral pixels adjacent to a correction object pixel in edges by using correction parameters Ka, Kb, Kc, and Kd. It is possible to independently determine each of the four correction parameters Ka, Kb, Kc, and Kd. Accordingly, even if there is directivity in a mixed color caused from peripheral pixels with respect to a pixel of interest, it is configured to enable mixed color correction corresponding to the directivity to be achieved.
An imaging device described in PTL 2 includes a coefficient table in which a correction coefficient related to a signal component mixed to each of pixels from peripheral pixels thereof is stored by being associated with each of positions of the pixels in a pixel array in which a plurality of pixels are arranged in a row direction and a column direction. The imaging device described in PTL 2 reads a corresponding correction coefficient from the coefficient table in accordance with a position of a correction object pixel so as to correct a signal of the correction object pixel by using signals of peripheral pixels thereof and the correction coefficient.